The present invention relates generally to electronic circuits for audio systems. More particularly, embodiments of the present invention provide circuits and systems for an integrated headset switch with reduced crosstalk noise.
With the advancement of electronics and integrated circuits, great progress has also been made in audio systems used in entertainment, computer systems, communication, electronic games, and mobile computing devices, etc. In advanced audio systems with features such as stereo sound, 3-D sound, and noise cancelation, the demand for quality is even higher. The quality of an audio system is measured by many parameters, for example, frequency response, harmonic distortion, output power, noise, and crosstalk, etc.
In electronics, crosstalk occurs when a signal transmitted on one circuit or channel of a system creates an undesired effect in another circuit or channel. Crosstalk is usually caused by undesired coupling from one circuit to another and can be especially prevalent in audio systems that include multiple speakers and/or a microphone. For example, headphones are a pair of small loudspeakers that are designed to be held close to a user's ears. Headphones either have wires or have a wireless receiver for connection to a signal source such as an audio amplifier, radio, CD player, portable media player, or mobile phone. Modern headphones have been particularly widely sold and used for listening to stereo recordings. Headphones are also useful for video games that use 3D positional audio processing algorithms, as they allow players to better judge the position of an off-screen sound source.
Multiple speakers are also used in surround sound, which is a technique for enriching the sound reproduction quality of an audio source with additional audio channels from speakers that surround the listener. Typically this is achieved by using multiple discrete audio channels routed to an array of loudspeakers.
Modern headsets often include a microphone for voice inputs in applications such as mobile devices and computers. The inclusion of a microphone in a headset can further complicate performance issues including crosstalk.
As described below, an audio system having two or more speakers and a microphone often are susceptible to crosstalk noise. Therefore, improved techniques for reducing the crosstalk noise in an audio system are highly desired.